Cmap. Franz et al., Bile salt hydrolase activity of enterococci isolated from food: Screening and quantitative determination, J FOOD PROT, 64(5), 2001, pp. 725-729
One hundred seventeen enterococcal strains isolated from food (47 Enterococ
cus faecium, 48 Enterococcus faecalis, 16 Enterococcus durans, 2 Enterococc
us gallinarum, 3 Enterococcus casseliflavus, and 1 Enterococcus malodoratus
) were screened for bile salt hydrolase (BSH) activity on de Man, Rogosa, a
nd Sharpe agar medium containing taurocholic acid and calcium chloride. The
highest incidence of BSH-active strains was observed for E. faecalis (81%)
followed by E. faecium (50%) and E, durans (44%). Isolates were grouped in
to four putative activity groups (no, low, medium, and high activity) based
on the size of precipitation zones observed in the screening experiment. O
ur results showed that assumptions on BSH activity based on the size of bil
e precipitation zones in screening experiments did not correlate with actua
l activity as quantified by high-pressure liquid chromatography, but the sc
reening assay is useful for assessing the presence or absence of BSH activi
ty.